textproduct: Quad Cities

KEY MESSAGES

- Several cold fronts pushing down across the region will make for seasonably cooler air across the area for much of the week ahead with highs in the 70s to low 80s, and lows in 50s to low 60s.

- Scattered showers and isolated thunderstorms are possible early Tuesday morning, with only light rainfall amounts expected.

- A seasonably strong system will bring the potential for severe thunderstorms on Wednesday. An Enhanced Risk (Level 3 of 5) of severe thunderstorms is in effect for areas south of Highway 34, with the remainder of the area under a Slight (Level 2 of 5) risk.

SHORT TERM /THROUGH TUESDAY NIGHT/

Issued at 145 PM CDT Mon Jun 15 2026

A shortwave trough is forecast to track across the Midwest tonight into Tuesday morning, dragging a cold front through eastern Iowa and northwest Illinois. This will bring a chance for scattered showers and isolated thunderstorms mainly between 3 AM - 9 AM on Tuesday. Rainfall amounts will remain light as the cold front will quickly shift through the area and low-level moisture will be limited per forecast soundings and model time- height sections. Tuesday will be another nice June day with breezy west-northwest winds (gusts around 30 mph) and highs in the mid/upper 70s.

LONG TERM /WEDNESDAY THROUGH MONDAY/

Issued at 145 PM CDT Mon Jun 15 2026

The extended discussion remains on track with the primary focus for severe storms being on Wednesday. The main story in the long term is a dynamically strong system forecast for Wednesday. Aloft, a shortwave coupled with a seasonably strong 500 mb jet of 65+ kts will move into the region. This, combined with a strong 850 mb jet, will provide a high-shear environment with over 60 kts of bulk shear. Ahead of this shortwave, southerly winds are expected to increase, with gusts potentially reaching 35-40 mph at times. This will support moisture return overnight through Wednesday morning, with guidance suggesting PWATs of 1.5-2.0 inches moving into the area. On top of this highly sheared and moist environment, mid-level lapse rates of 8+ degC/km suggest the potential for a dynamically charged and unstable environment supportive of severe thunderstorms. As a result, SPC has an Enhanced (Level 3 of 5) risk of severe storms for areas south of Highway 34, with the remainder of the area under a Slight (Level 2 of 5) risk.

However, some uncertainty could limit the severe potential. The most likely limiting factor to severe potential is the moisture return. While the models suggest a large pool of moisture available across the region, the shortwave shifting latitude or speeding up/slowing down could limit how much moisture reaches the area. Guidance agrees largely on the track of the surface low moving across central Minnesota, with a few pulling it farther south along the Iowa-Minnesota border. With this track, if the system were to speed up, the axis of greatest moisture would tilt eastward, leaving the greatest moisture to our south. Additional areas of uncertainty, including potential for convection earlier in the day, will become more apparent as we approach Wednesday.

Past Wednesday, the forecast looks to be calmer as we return to the background northwesterly flow behind the departing system. High pressure will slide in Thursday from the northwest, interrupted briefly by a shortwave that could bring our next round of rain Thursday into Friday if we have ample moisture return. Otherwise, we will remain under the influence of high pressure through the weekend.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 653 PM CDT Mon Jun 15 2026

Largely VFR conditions are expected through the TAF period. The main focus continues to be overnight tonight as a cold front is expected to sweep through the area after midnight. Along the front, a relatively short period of low-level wind shear is expected as winds around 2kft strengthen. Additionally, some light showers can't be ruled out, which may be heavy enough to generate high-end MVFR visibility reductions. Model ensembles suggest lower chances of accumulating rainfall (around 30%), so continued using PROB30 groups to highlight the timing and impacts of these showers. The front should pass through quickly, leading to winds turning from the northwest and strengthening to around 20 to 30 knots late Tuesday morning through the afternoon.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.